Prostaglandins having the structure ##STR1## wherein R.sub.1 is hydrogen or loweralkyl having 1-4 carbon atoms; R.sub.2 and R.sub.3 is hydrogen or loweralkanoyl being 1-4 carbon atoms R.sub.4 is loweralkyl having 1-4 carbon atoms, and X is --CH.sub.2 --CH.sub.2 -- or --CH.dbd.CH-- are known compounds having utility in the treatment of peptic ulcer disease. The compounds, their preparation, and use in the treatment of ulcers are described in U.S. Pat. Nos. 3,965,143, 4,060,691 and 4,087,621. These patents are incorporated by reference in this specification.
Jacotot and Gero Path Biol 23 711-715 (1975) describe the effect of prostaglandin PGE.sub.1 on blood and tissue lipids in rabbit experimental atherosclerosis. The 16-loweralkyl-16-hydroxy prostaglandins used in the methods of this invention lower elevated cholesterol levels to normal levels in patients with hypercholesterolemia and without effectively lowering normal cholesterol levels. Thus a new medical use of known compounds has been discovered.